Hi Tim, I believe that it runs into an issue which is specific to cloudera release we fixed recently. For details, could you discuss it in cdh forum? Copy me(h...@cloudera.com <mailto:h...@cloudera.com>) in the forum so I can explain more there.
Thanks, Huaxiang > On Oct 12, 2016, at 8:13 AM, Ted Yu <yuzhih...@gmail.com> wrote: > > Have you looked at HBASE-16578 ? > > Cheers > >> On Oct 12, 2016, at 8:02 AM, Tim Robertson <timrobertson...@gmail.com> wrote: >> >> Hi devs, >> [Had a quick chat with Lars G. about this and before opening a Jira I >> thought I'd raise it here first] >> >> We have just experienced data loss in HBase 1.0.0-cdh5.4.10. >> >> Before I dig into this further, I'd like to just ask if anyone has seen >> this before? >> >> The initial state was a table (tim_test) built with MOB support and a few >> 10's million rows and 10's billions of cells. >> >> I wanted to rename the table to get this into production and did so as >> follows: >> >> snapshot 'tim_test', 'tim_test-snapshot' >> clone_snapshot 'tim_test-snapshot', 'prod_b_map' >> >> At this stage the application all looked good, and so I continued with: >> >> delete_snapshot 'tim_test-snapshot' >> disable 'tim_test' >> drop ‘tim_test’ >> >> Then things went... awry and data just started dropping out in the app. >> Before long, all MOB data seemingly is gone. >> >> The references in the new table MOB folder appear to point to the source >> table (e.g. >> /hbase/mobdir/data/default/prod_b_map/ba42a2e8e9b669d9fc85bdfeed2f5f2a/EPSG_4326/tim_test=14bf5f1737ac65c34615ed97c0b7de06-d41d8cd98f00b204e9800998ecf8427e20161006ff8baa70d21f408caefe8ae6318dfba2). >> >> The RS logs full of ERROR like: >> >> 2016-10-12 15:19:14,640 ERROR org.apache.hadoop.hbase.regionserver.HStore: >> The mob file >> d41d8cd98f00b204e9800998ecf8427e20161006b59865f80e604781a79ebfa2ddd66b48 >> could not be found in the locations >> [hdfs://ha-nn/hbase/mobdir/data/default/tim_test/14bf5f1737ac65c34615ed97c0b7de06/EPSG_4326, >> hdfs://ha-nn/hbase/archive/data/default/tim_test/14bf5f1737ac65c34615ed97c0b7de06/EPSG_4326] >> >> What I don't know is: >> 1) was this running a background task to copy the MOB data when the >> snapshot was cloned and I just deleted the source before the copy was >> complete? >> - or >> 2) when running "snapshot and clone" it just references the source MOB >> data until a (?) change? >> 3) snapshot and clone just doesn't support MOB? >> >> Can anyone shed some light on this easily before I dig into it please? >> >> While this situation exists (at least in 1.0.0) might it be good to get >> info about data loss for MOB tables into the snapshot clone docs? >> >> Thanks, >> Tim
